Electric singeing-furnace



0. A. COLBY.

ELECTRIC SINGEING FURNACE.

APPLICATION FILED OCT 30| I9I8.

Patented Apr. 27, 1920.

L C :I I I I INVENTOR 0rd A. o/y

ATTRNEY WITNESSES:

UNITED STATES PATENT OFFICE.

ORAA. COLBY, OF LARIMER, PENNSYLVANIA, ASSIG-NOR T0 WESTINGHOUSE ELECTRIC &.MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELECTRIC SINGEING-FURNACE.

Application filed October 30, 1918.

To all whom z't may concern Be it known that I, ORA A. COLBY, a citiyzen of the United States, and a resident of Larimer, in the county of Westmoreland and State of Pennsylvania, have invented a new and useful Improvement in Electric Singeing-Furnaces, of which the following is a specification.

My invention relates to electrically heated furnaces and has particular vrelation to that type of furnace which is used to perform the singeing operation upon cloth or other fabric. y

In singeing the nap from a piece of cloth, it-is essential that the temperature of the element over which the clothis passed be maintained substantially uniform, since, otherwise, the cloth is singed unevenly and is thereafter commercially undesirable.

In the past, one of the principal disadvantages encountered in singeing the nap from cloth has been this nonuniformity of the heating, especially when the singeing was accomplished by means of small flames which were positioned in proximity to the cloth. Under these circumstances, the cloth was frequently singed so irregularly that it presented an undesirable appearance. It is obvious why it is not an easy matter to obtain a uniform temperature over the entire surface of the cloth to be treated when a gas-heated, singeing apparatus is used.

However, by the use of a furnace in which electrical power is employed for heating the singeing element over which the cloth is passed, I am able to maintain a uniform temperature t roughout the entire surface of such singeing element and, therefore, to insure that the nap of the cloth passing over this singeing elementl shall be evenly removed.

Moreo`ver, by the use of electrical power, I obtain all of those advantages which are incident'to the employment of such power,

necessary for the desired singeing operasuch, for instance, as lower cost and maintenance and ready accessibility for the purpose of repairs, as well as other advantages which will hereinafter appear.

For a better understanding of my invention, reference may be had to the accompanying drawing in which Figure 1 is a horizontal sectional view of a furnace constructed in accordance with my invention, while Fig. 2 is` a vertical sectional view taken along the line I I of Fig. 1.

Specicationof Letters Patent.

Patented Apr. Z7, 1920.

serial No. 260,279.

Referring now more particularly to the drawings, the furnace comprises a frame or body portion 1 supported upon vertical legs or standards 2 2. Electrodes 3 3, composed of carbonaceous material, are shown extending longitudinally through the furnace from end to end and as adapted for connection to any suitable source of electrical power.

Columns 4 4 of granular graphite or carbon are. shown as extending vertically upward from the electrodes l3 and as being in close contact therewith. At the upper endsof the columns 4 are resistors 5 5, shown here as bridging the upwardlyextending columns 4, and thus establishing an electrical path for the power which is supplied to the electrodes 3.

The resistors 5 5 comprise a plurality oftransversely extending blocks 6 6 of silicon carbid. It will benoted, by thereference to Fig. 1, that the blocks 6 are so posi tionedthat one or more of them may be removed at any desired point 4in the resistor, and the resistance of the combined blocks may be thereby increased. In this manner, it is a relatively simple matter to vary, to any predetermined degree, the amount of power taken by the furnace and the consequent amount of heat delivered by the resistors 5 5. CurvedA cover plates 7 7, having their convex surfaces exposed to the air, are provided with flanges 8-8, these flanges rest-4 ing on the small nonconducting bars 9 9. By means of this arrangement, the weight of the cover plates 7 7 is utilized to a maximum degree in maintaining an air-tight connection between the columns 4 4 andv the resistor blocks 6 6.'

Having described a furnace constructed in accordance with my invention, the operation is as follows:

Having determined the degree of heat contact with the convex surfaces, the nap is smoothly burned from its entire surface.

It will be understood that, should it be desired to singe the nap from both sides of the cloth two of the furnaces here shown may be employed -and any suitable system of reversing rollers be so associated with the furnaces that the two sides of theJ` cloth shall be singed, as desired.

It will be noted that the electrodes are at a maximum distance from the heating elements, and, therefore, that the possibility of the electrodes being burned away is greatly lessened. Moreover', by locating heavy metal plates above the electrodes and the granular columns and pressing the same together, I am able to maintain such con.- tactA between the various :conducting elements of the furnace as' to avoid arcing or other disturbance which might otherwise result from loose or faulty connections.

When the granular material of which the vertical, resistor-supporting columns are composed is consumed, it may be easily replacedbecause of the facility with which the metal cover plate may be removed. Moreover, the ready removability of the coverplates is also available to vary, in any desired manner, the degree of heat gen-` erated, since, by removing the plates, the resistor blocks of which the bridging resistor is composed, may be removed one by one at predetermined points and the degree of heat applied to the portions across the width of a bolt of cloth may thereby be varied. This removability of the plates'is also utilized when it is desired to singe cloth which may become glossy by contact with the plates. The heat radiated by the bare resistors is then used to perform the sinfreing operation.

hile I have shown but one form of my invention, it is obvious that many modifications may occur to those skilled in the art, and I desire, therefore, that only such limitations shall be placed thereon as are imposed by the scope of the prior art or are specified in the appended claims.

I claim as my invention:

1. In an electric furnace adapted for singeing cloth, the combination of a resistor comprising a plurality of transversely extending conducting blocks, heat-insulating means covering the sides and the bottom of said resistor, and means overlying said resistor whereby heat may be transferred uniformly frpm said resistor to the surface of said cloth.

2. In an electric furnace,y the combination of singeing means, a resistor, and embodying means in said resistor made accessible by the removal of said singeing means whereby the power input of said furnace may be varied.

3. In an electric furnace, the combination.

4. In an electric furnace, the combination of a resistor, terminal electrodes, masses of granular conducting material interposed between said electrodes and said resistor, and means maintaining an air-tight connection between said resistor and said granular masses.

5. In an electric furnace, the combination of a resistor comprising a plurality of vtransversely extending conducting blocks,

terminal electrodes, masses of granular conducting material interposed between said resistor and said electrodes, and a singeing element overlying said resistor.

6. In an electric furnace, the combination of a resistor comprising a plurality of transversely extending conducting blocks, terminal electrodes, masses of granular conducting material interposed between .said resistor and said electrodes, and a singeing element overlying said resistor and, by its weight, maintaining an air-tight connection between said resistor and said granular masses.

7. In anelectric furnace, the combination of terminal electrodes, granular conducting masses disposed in Contact with said electrodes, a resistor positioned above said granular masses, and a heat-emitting element` overlying said resistor, said resistor being maintained in air-tight connection with said ganular masses by said heating element.

8. In an electric furnace, the combination of terminal electrodes, granular conducting masses disposed in contact with, and extending above, said electrodes, a resistor positioned above and bridging said granular masses, and a heat-emitting element overlying said resistor, said resistor being maintained in air-tight connection with said granular masses by said heating element.

In testimony whereof I have hereunto subscribed my name this 17th day of Oct.,

ORA A. COLBY. 

